Fumaric acid esters in psoriasis and multiple sclerosis

Transcriptomic Analysis of Fumarate Compounds Identifies Unique Effects of Isosorbide Di-(Methyl Fumarate) on NRF2, NF-kappaB and IRF1 Pathway Genes

Dimethyl fumarate (DMF) has emerged as a first-line therapy for relapsing-remitting multiple sclerosis (RRMS). This treatment, however, has been limited by adverse effects, which has prompted development of novel derivatives with improved tolerability. We compared the effects of fumarates on gene expression in astrocytes. Our analysis included diroximel fumarate (DRF) and its metabolite monomethyl fumarate (MMF), along with a novel compound isosorbide di-(methyl fumarate) (IDMF). Treatment with IDMF resulted in the largest number of differentially expressed genes. The effects of DRF and MMF were consistent with NRF2 activation and NF-κB inhibition, respectively. IDMF responses, however, were concordant with both NRF2 activation and NF-κB inhibition, and we confirmed IDMF-mediated NF-κB inhibition using a reporter assay. IDMF also down-regulated IRF1 expression and IDMF-decreased gene promoters were enriched with IRF1 recognition sequences. Genes altered by each fumarate overlapped significantly with those near loci from MS genetic association studies, but IDMF had the strongest overall effect on MS-associated genes. These results show that next-generation fumarates, such as DRF and IDMF, have effects differing from those of the MMF metabolite. Our findings support a model in which IDMF attenuates oxidative stress via NRF2 activation, with suppression of NF-κB and IRF1 contributing to mitigation of inflammation and pyroptosis.

Treatment approaches to patients with multiple sclerosis and coexisting autoimmune disorders

The past decades have yielded major therapeutic advances in many autoimmune conditions - such as multiple sclerosis (MS) - and thus ushered in a new era of more targeted and increasingly potent immunotherapies. Yet this growing arsenal of therapeutic immune interventions has also rendered therapy much more challenging for the attending physician, especially when treating patients with more than one autoimmune condition. Importantly, some therapeutic strategies are either approved for several autoimmune disorders or may be repurposed for other conditions, therefore opening new curative possibilities in related fields. In this article, we especially focus on frequent and therapeutically relevant concomitant autoimmune conditions faced by neurologists when treating patients with MS, namely psoriasis, rheumatoid arthritis and inflammatory bowel diseases. We provide an overview of the available disease-modifying therapies, highlight possible contraindications, show pathophysiological overlaps and finally present which therapeutics can be utilized as a combinatory treatment, in order to 'kill two birds with one stone'.

Fumaric acid: a possible new therapy for macular edema?

INTRODUCTION

Causes of macular edema are multifactorial, but inflammation, vascular factors and mechanical traction are of major importance. Therapeutic options of macular edema depend on the underlying cause. Intravitreal administration of inhibitors of vascular endothelial growth factor leads to inhibition of retinal neovascularization and subsequent edema.

OBJECTIVE

Fumaric acid esters are successfully used in dermatology for years according to their antiangiogenic and anti-inflammatory effects.

RESULT

For the very first time, we describe a successful therapeutic attempt for macular edema, controlled by optical coherence tomography using fumaric acid esters followed up for 60 months.

Controlling the pro-inflammatory function of 6-sulfo LacNAc (slan) dendritic cells with dimethylfumarate

BACKROUND

The fumaric acid ester (FAE) dimethylfumarate (DMF) is a small molecule immunomodulator successfully used for the treatment of psoriasis and multiple sclerosis (MS). DMF is thought to inhibit pathogenic immune responses with Th17/Th1T cells, and IL-23/IL-12 producing dendritic cells (DCs). 6-sulfo LacNAc expressing dendritic cells (slanDCs) are a human pro-inflammatory cell type found frequently among the infiltrating leukocytes in skin lesions of psoriasis and brain lesions of MS.

OBJECTIVE

To explore the influence of DMF on functional properties and cell signaling pathways of slanDCs.

METHODS

In the context of slanDCs we studied the role of DMF in modulating cell migration, phenotypic maturation, cytokine production, cell signaling and T cell stimulation.

RESULTS

Initially, we observed the reduction of slanDCs numbers in psoriasis skin lesions of FAE treated patients. Studying whether DMF controls the migratory capacity of slanDCs to chemotactic factors expressed in psoriasis we observed an inhibition of the CX3CL1 and C5a depedent cell migration. DMF also attenuated the rapid spontaneous phenotypic maturation of slanDCs, as judged by a reduced CD80, CD86, CD83 and HLA-DR expression. In addition, we observed a DMF-dependent decrease of IL-23, IL-12, TNF-α and IL-10 secretion, and noticed a reduced capacity to stimulate Th17/Th1 responses. DMF targeted in slanDCs different intracellular cell signaling pathways including NFκB, STAT1 and HO-1.

CONCLUSIONS

With this study we identify a frequent pro-inflammatory cell type found in psoriasis and MS as a relevant target for the therapeutic immunomodulatory effects of DMF.

Fumaric acid esters in the management of psoriasis

Fumaric acid esters (FAE) are small molecules with immunomodulating, anti-inflammatory, and anti-oxidative effects. FAE were introduced as a systemic psoriasis treatment in 1959 and empirically developed further between 1970 and 1990 in Germany, Switzerland, and the Netherlands. The development of FAE as psoriasis treatment did not follow the traditional drug development phases. Nonetheless, in 1994 FAE were approved in Germany for the treatment of severe plaque psoriasis. FAE are currently one of the most commonly used treatments in Germany, and FAE are increasingly being used as an unlicensed treatment in several other European countries. To date, six randomized controlled trials and 29 observational studies have evaluated FAE in a combined total of 3,439 patients. The efficacy and safety profile of FAE is favorable. About 50%-70% of patients achieve at least 75% improvement in psoriasis severity after 16 weeks of treatment. Common adverse events of FAE include gastrointestinal complaints and flushing symptoms, which lead to treatment discontinuation in up to 40% of patients. Lymphocytopenia, eosinophilia, and proteinuria are commonly observed during FAE treatment, but rarely require treatment discontinuation. The long-term safety profile of continuous FAE treatment is favorable without an increased risk for infections, malignancies, or other serious adverse events. There are no known drug-interactions for FAE. The 2009 European evidence-based S3-guidelines on psoriasis treatment recommend FAE and suggest it as a first-line systemic treatment for moderate-to-severe plaque psoriasis. This review is aimed to give an overview of FAE treatment in the management of psoriasis.